Nettles in aquaculture setup

Hey, wondering if anyone had any insight about possible effects on goldfish in an aquaculture set up where nettles are being grown.

We had a die off after planting some, and admittedly we weren't monitoring conditions well enough to rule out other culprits, but my husband has a theory and it involves my beloved stingy plants.  


What do you all think?

The rhizomes are well established and we've delayed adding more fishes until I remove them. Our first water measurements  were after some months of no fish, and all the water levels are great now. Should I remove the nettle or give goldfish another go with them?

Thanks!

What is the volume of water in your pond?  How many fish did you introduce?  How many died off?  Was your pond aerated? What was the air and water temperature at the time of die off? What is the proximity of the nettles to the pond edge?

Without aeration, the heat of the summer, volume of fish/water can lead to oxygen deprivation and die-off.

Angela Wilcox wrote:What is the volume of water in your pond?  How many fish did you introduce?  How many died off?  Was your pond aerated? What was the air and water temperature at the time of die off? What is the proximity of the nettles to the pond edge?

Without aeration, the heat of the summer, volume of fish/water can lead to oxygen deprivation and die-off.

We are growing the nettles in hydroton in halved barrels, water is pumped up through pvc pipes from totes below holding the goldfish. There are two connected totes each holding 50 gallons for 100 total gallons, and they contained 50 total goldfish. All fish died. We had heat and aeration, though we weren't monitoring too closely so we can't be sure nothing malfunctioned. This system functioned fine through 4 seasons before the die off, which occurred a few months after nettles were introduced.  

I know I'm asking a question that introduces a lot of speculative variables that I don't have answers to because of poor tending, but I'm hoping some one would be able to shed light on whether it is likely that the chemicals that make nettle stingy became bioavailble and harmful to the fishes.

Leslie Masciocchi wrote:

Angela Wilcox wrote:What is the volume of water in your pond?  How many fish did you introduce?  How many died off?  Was your pond aerated? What was the air and water temperature at the time of die off? What is the proximity of the nettles to the pond edge?

Without aeration, the heat of the summer, volume of fish/water can lead to oxygen deprivation and die-off.

We are growing the nettles in hydroton in halved barrels, water is pumped up through pvc pipes from totes below holding the goldfish. There are two connected totes each holding 50 gallons for 100 total gallons, and they contained 50 total goldfish. All fish died. We had heat and aeration, though we weren't monitoring too closely so we can't be sure nothing malfunctioned. This system functioned fine through 4 seasons before the die off, which occurred a few months after nettles were introduced.  

I know I'm asking a question that introduces a lot of speculative variables that I don't have answers to because of poor tending, but I'm hoping some one would be able to shed light on whether it is likely that the chemicals that make nettle stingy became bioavailble and harmful to the fishes.

Great question. Thank you for the extended details. I hope you get some input here.

The problem could have been extra fertilizer in the soil that the nettles brought to the system, it could have been microbes that the nettles brought to the system. or it could be that the nettles themselves are releasing some compounds that harmed the fishes. Maybe the nettles always release that compound, maybe they only release it when they are young, maybe they only release when they are eaten/hurt/moved/threaten. Maybe it is all of the above combined that did the fish in, but any one or two by itself would have been fine. I think that if you added baby fish they would survive.